Apparatus for the continuous treatment of filamentary material



Nov. 18,1952 R. LIPSCOMB APPARATUS FOR THE CONTINUOUS TREATMENT OFFILAMENTARY MATERIAL Filed April 7, 1949 Inventor ROBERT LIPSCOMBAttorneys v Patented Nov. 18, 1952 APPARATUS FOR THE CONTINUOUS TREAT-MENT OF FILAMENTARY MATERIAL Robert Iaipscomb, Welwyn, England, assignorto Imperial Chemical Industries Limited, a corporation of Great BritainApplication April 7, 1949, Serial No. 86,072 r In Great Britain April19, 1948 p 14 Claims. (01. 190.46l

This invention relates to an improved process for subjecting continuouslengths of filamentary material to .a number of after-spinningtreatments in one continuous'operation.

In the production of artificial filaments for use for such purposes assynthetic bristles or fishing lines,nit is necessary after the actualspinning operation to subject the filaments to various after spinningtreatments. ,In the production of nylon filament, for example, thefollowing steps are required. The filament after drawing undergoes aconditioning treatment in boiling wateror steam, drying and finallyguillotining into short lengths. [At the present time this is commonlydone by a number of separate steps. For example the nylon filament fromthe spinneret passes through a quenching bath and is then wound onto abobbin. From this bobbin it is unwound and subjected to drawing. Afterdrawing the filament is wound onto a beam on which it is subjected to aconditioning treatment. Finally the filaments are cut at one end of thebeam and after removal from the beam the hank is dried and then thecurled j ends are removed by a guillotine leaving a bundle of lengths offilaments, each about four feet long. It will be appreciated that theoperation of all the above steps involves considerable manual labour andtake 'a long time;

An object of the present invention is the provision .of a processwherein a continuous filamentary material may be subjected to a numberof different treatments in one continuous operation.- A further objectisthe provision of such a process which involves a minimum amount ofmanual labour. A still further object is the provision of one continuousprocess in which all the steps in the after-spinning treatment ofcontinuous artificial filaments may be carried out.

According to the present inventionthes'e objects are accomplished by aprocess wherein a continuous artificial filament is laced in a zig-zagpath between two lines of pegs, spaced apart and side by side,projecting from an endless conveyor which carries the pegs and thefilament through various treating zones to a receiver- In the treatmentof an artificial filament it is preferable to lace the filament aroundthe pegs as it comes from the spinning orifice. This enables thespinning and treating of artificial filaments to take place in onecontinuous process.

In many cases the lines of pegs will be substantially parallel but thisis by no means essential. Indeed, in a preferredmodification,particularly suited for the after-spinning treatment of nylon filament,the lines of pegs travel parallel for a l 2 I portionof their'journey,then diverge so that filaments laced around the pegs are drawn. They mayalso gradually diverge to draw the filament gradually, or converge toallow the filament to relax. I

In the following example, which illustrates but does not limit the scopeof our invention, a nylon filament is treated on a preferred type ofapparatus. The apparatus, which is shown in the attached drawings, takesthe place of the drawing machine, beam winder, conditioning tank,guillotine and drying oven commonly used in the manufacture of nylonfilament for use'in the production of artificial bristles. Figure 1 is adiagrammatic plan view of the apparatus, not to scale, Figure 2 is avertical section through the line zv :r in Figure 1.

Example The conveyor'in this process consists of two heavy conveyorchains I, of 5 inch pitch driven round sprockets 2 and 2A, mounted inpairs on vertical shafts 3, as shown in Figure 2, so as to rotate in ahorizontal plane.

The upper surfaces of the two chains rotate in the same horizontal planeand the chains follow a path such that over a portion of their lengththey travel parallel and 2 feet apart then diverge to a distance of 8feet apart and finally continue parallel and 8 feet apartfor a furtherportion of their length before passing round sprockets and returning totheir starting point. On the upper surfaceof the chains, short steelpegsl, each two inches high, project upwards from the plates of thechain links. These pegs resemble bollards in shape being waisted in themiddle to diameter and being larger in diameter above and below thiswaist.

Nylon filament 5, from the quenching bath, below the spinneret, passesthrough'the guide of a traverse feeder mechanism (not shown) to the pegson the chain conveyor mechanism. The continuous filament is fastenedround one peg and the pegs during this drawing operation and providingnon-uniform filaments, two rubber wheels 6, mounted on the same shaft asthe sprockets 2A, press the filament into contact with the pegs over theportion of the chain length where drawing commences as shown in Figure2.

When drawing is completed the drawn filament is carried by the chainsthrough a conditioning chamber 8 into which steam is passed and theninto a second chamber 9, where a current of hot air dries the filament.At the end of this machine the filament leaves the drier and is conveyedto the receiver where the stretched span of the filament meets rotatingknives 1, rotating in parallel planes at right angles to the filament,which cut the filament into short lengths. To prevent the filamentslipping after cutting, the filament is again held against the pegs bymeans or rubber wheels 6 above the sprockets 2A and on the same shaftswhich press the filament on the pegs during the cutting operation. Thecut lengths of straight filament fall into a tray and can be bundledwithout difficulty. The length of the cut pieces may be varied byvariation of the position of the knives and additional knives may bemounted between the two shown if desired.

While in the foregoing description particular reference has been made tonylon it will be appreciated that the apparatus may be applied to allartificial filament forming material.

The type of treating zone used will obviously depend upon the filamentbeing treated. The apparatus used for the construction of the zones, i.e. liquid bath or gas or vapour tunnels is that commonly used in theart.

While in the apparatus described the material comes direct from thespinneret to the conveyor this is not essential. The filamentarymaterial may be reeled and then fed to the conveyor if desired.

The peg dimensions and constituent material will depend upon thefilamentary material being treated and so too will-the material andconstruction of the conveyor. Pegs should be constructed of hard wearingmaterial otherwisefrequent replacements will be required. For thetreatment of filaments when no drawing operation is required broadconveyor bands carrying both lines of pegs may be used. If however adrawing operation is required or if the filament is subjected to atreatment which results in shrinkage, heavy conveyor chains mounted onsprockets are preferred as the forces used in the drawing operation andexerted during shrinkage, may be very great.

The shape of the peg is only limited by the fact that the filament mustbe laced from one line to the other. The waisted bollard shaped p'eg ispreferred as it permits easy lacing and also prevents the filamentslipping from the peg. The chains may follow any desired path and neednot carry the filament in a horizontal plane.

The path may be accurately and firmly prescribed by means of sprocketsand guides.

During the cutting or drawing operation utilising the apparatusdescribed hereinbefore, rubber wheels are used to prevent the filamentslipping over the peg surface. It will be appreciated that the wheelsneed not be made wholly of rubber or like resilient material but mayhave a metal centrepart with a resilient tyre.

Although only two cutting wheels are shown in the example any number maybe used, depending upon the length of filament required.

Tapered filaments, which are used in the production of artificialbristles, may be treated using the apparatus of this invention. Intreating tapered filaments the position of the filaments on the pegs iscontrolled so that the portion passing round a peg of the machine isalways in the same part of the taper, e. g. midway along the thickportion of the filament (the width between the lines of pegs being madea multiple of the taper pitch) to ensure that the rotating knives arelocated so that they always out the strands at the same part of thetaper, e. g. midway along the thick or thin portion and so that the cutpieces are all in phase with each other.

The process is particularly suited for treating artificial filaments ofnylon or of one of the highly polymerised polymethylene terephthalatesdescribed and claimed in British specifications Numbers 578,079 and590,451.

Utilising the process of this invention reduces the cost of theafter-spinning treatment of artificial filamentary materialconsiderably, the manual operationsbeing reduced to a' minimum.Furthermore the final product is homogeneous and is collected in a formvery suitable for packaging with the minimum amount of waste.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed I declare thatwhat I claim is:

l. A process for the production of short lengths from artificialfilamentary material of continuous character and capable of being colddrawn which comprises lacing a continuous filament in a substantiallyzig-zag path between two series of points the locus of which constitutestwo lines lying in a plane, drawing the laced filament by causing saidpoints to diverge at a position beyond the position of said lacing ofthe filament between said points then passing the drawn filament throughtreating zones to a position where the treated filament, while beingheld between said diverged points is cut in at least two places alongthe length of the filament portions held between said diverged points,the maximum length of filament cut being determined by the distanceapart of said series of points.

2, A process according to claim 1 wherein the lines of points areparallel during at least part of the process.

3. A process according to claim 1 wherein the filament comes to theconveyor direct from the spinneret.

4. A process according to claim 1 wherein the filament is an artificialtapered filament and the distance between the lines of points is suchthat the portion of the filament in contact with the points is alwaysthe same part of the taper.

5. A process according to claim 1 wherein the filament is of nylon.

6. A process according to claim l'wherein the filament is composed ofhighly polymerised polymethylene terephthalate.

7. Apparatus for the continuous production of short lengths of colddrawn artificial filamentary material from a contniuous' lengthofundrawn material laced in zig-zag fashion between two lines of pegs inthe same plane, which comprises a pair of endless conveyors which arespaced apart and sideby side, and which carry said two lines of pegs,means for causing said endless conveyors to diverge so that the distancebetween the lines of pegs increases to draw said filament, treatingchambers through which the drawn filament is carried by said endlessconveyors ta g I smash point where at least two cutting wheels, rotatingin planes substantially at right angles to the filament, cut thefilament into'short lengths, and a container to collect the cut lengths.

8. Apparatus according to claim 7 wherein the pegs are waisted toprevent the filament slippi s o 9. Apparatus according .to claim 7wherein the lines 01' pegs are parallel during at least part of the timewhen they are conveying the filament.

10. Apparatus according to claim 7 wherein wheels having a perimeter ofrubber or like re silient material press the filament against the pe s.

11. Apparatus according to claim 7 wherein the conveyor consists of twoendless chains rotating in a plane, around sprockets with the pegsprojecting in the same direction from plates of the links of eachchain.the chains being caused to diverge by the suitable positioning of thesprockets. v

12. Apparatus according to claim 7 wherein one 0! the treating chambersis a steam chamber. 13. Apparatus according to claim 7' wherein one ofthe treating chambers is a hot air oven. 14. Apparatus according toclaim 7 wherein the cut lengths fall onto a moving band.

ROBERT LIPSCQMB.

REFERENCES CITED The following references are of record in the file ofthis patent:

